Should I Take Omega 3 or Fish Oil for Heart Health?
February 04 2022
Omega-3 or fish oils are one of the most popular supplements making over a billion in annual sales. One of the most talked about benefits of omega-3 is for your heart. But are there any benefits? Let’s take a closer look
What do recent trials on Omega-3 & heart health show?
Let’s look at some of the recent trials on Omega-3 and heart health:
For people with/at risk of heart disease:
ASCEND trial (2018):15,480 patients with diabetes but with heart disease received 1 gm of omega 3 or placebo. After 7.4 years, Omega-3 did not reduce the primary cardiovascular endpoints
STRENTH trial (2020): 13K patients with heart disease or high risk of heart disease took 4 g daily of EPA/DHA or corn oil placebo. After 42 months, no difference in heart disease events!
OMEMI trial (2021): 1000 older patients (mean age, 75) with recent myocardial infarction received either EPA/DHA (1.8 g daily) or placebo. At 2 years, there was little difference between the groups!
In the general population:
DO-HEALTH trial (2020): 2200 healthy older adults were randomized both to EPA/DHA (1 g daily) or placebo and to strength training or no training. After 3 yrs., no health benefits were seen
VITAL trial (2021): 25,871 participants, men 50 years of age or older at low risk of heart disease. After 5.3 years, little or no difference in major cardiovascular events.
In short, ALL studies were negative. And mind you, these were very well-designed, million-dollar studies over a long duration of 1-5 years. So, this isn’t the typical 30 subject, 12-week supplement study. I am just amazed how this keeps selling after so many negative trials!
Are there any recent positive omega 3 trials?
Yes. The landmark REDUCE-IT trial in 2018 that had 8K people taking statins who have high triglycerides showed a very impressive 25% reduction in cardiovascular events. But two major caveats:
- EPA: The omega 3 used only contained EPA and not the typical EPA + DHA combination that people often buy.
- Large dose: The dose used was 4 gms which is probably 5-6 times the dose of EPA found in typical store brand omega-3 supplements.
It appears that the benefit of omega-3 for health is primarily because of EPA and not the combo of EPA + DHA. Also, partially due to the corn oil used in the control group making the omega-3 group look better.
Any recent meta-analysis looking at omega 3 & heart health?
The 2020 Cochrane meta-analysis looked at 86 trials and showed little or no effect for most of the outcomes, such as deaths, cardiovascular deaths, and events and stroke. Omegas may have a small reduction in coronary heart disease events and deaths (coronary means related to the arteries to the heart). These effects did not differ by dosage either.
The table below shows 2 ways to present the number of people that will benefit with omega-3. For instance, for deaths, as shown below if 1000 people take omega-3, there will be 2 less deaths in 4 years. And number needed to treat (NNT) shows 500 people will have to take omega-3 for 4 years to prevent one death!
I am a proponent of meta-analysis, but when you meta-analyze studies that have thousands of subjects per study, you run the risk of making tiny effect to become statistically significant. Statistically significant, but practically meaningless.
What about the risk of Omega 3 and atrial fibrillation?
Atrial fibrillation or flutter involves irregular and rapid heartbeat that could lead to strokes and heart complications.
Atrial fibrillation was higher in the omega-3, with higher doses showing a significant risk (STRENGH & REDUCE-IT trial). What is high? For example, STRENTH trial showed a 62% increase with a higher dose of 4gms of EPA plus DHA. This means out of 1000, 9 more will get an AF. Other risks include bleeding and gastrointestinal issues, such as diarrhea.
So, should I take Omega- 3 for heart health?
- As shown by these recent trials and meta-analysis, there is little benefit to the Omega-3 in people with heart disease and without. (for people with high triglycerides on statins, high-dose EPA could be beneficial)
- On the other hand, there is a very small increase in the risk of atrial fibrillation with omega-3 at higher doses.
- Looking at the benefits and risks, I personally wouldn’t take Omega-3 for heart health. Would you?
